394 NAPHTHALENE. 



naphthalate. Colorless laminae ; fusing point, 66.5 ; 

 boiling point, 304-305. 



Nitronaphthalene, C W H 7 (^0 2 ), is formed by tbe 

 action of concentrated nitric acid on naphthalene ; 

 slowly at the ordinary temperature, rapidly by boiling. 

 Crystallizes from alcohol in sulphur-colored prisms ; 

 fusing point, 58.5, and sublimes when carefully 

 heated; insoluble in water, easily soluble in alcohol 

 and ether. 



a-Dinitronaphthalene and p-Dinitronaphthalene, 

 C 10 H 6 (N0 2 ) 2 , are produced simultaneously when the 

 preceding compound, or naphthalene, is boiled with 

 nitric acid until no oily body (melted nitronaphtha- 

 lene) can be detected on the surface of the liquid. 

 The two compounds may be separated by boiling with 

 alcohol, in which the a-compound is more easily solu- 

 ble; and crystallizing from chloroform. a-Dinitro- 

 naphthalene crystallizes in four- or six-sided rhombic 

 plates, that detonate when heated; fusing point, 170 ; 

 /3-dinitronaphthalene crystallizes in colorless, sublima- 

 ble prisms, that fuse at 214. If the boiling with 

 nitric acid is continued for several days trinitronaphtha- 

 lene, C 10 H 5 (^N"0 2 ) 3 , is formed ; small, monoclinate prisms, 

 fusing at 214. When this is heated for a long time 

 with fuming nitric acid in sealed tubes at 100, it is 

 converted into tetranitronaphthalene, C 10 H 4 (N0 2 ) 4 , which 

 crystallizes in fine needles, resembling asbestos; fusing 

 point, 200. 



Naphthylamine (Naphthalidine), C 10 H 7 .KH 2 , is 

 produced from nitronaphthalene in the same way that 

 anilin is produced from nitrobenzene (cf. p. 258). Fine, 

 colorless prisms, of an unpleasant odor; almost insolu- 

 ble in water, easily soluble in alcohol ; fuses at 50 ; 

 sublimes easily, and boils at 300. Turns ^gradually 

 red in contact with the air. Combines with acids, 

 forming crystallizing and, for the greater part, easily 

 soluble salts. Oxidizing agents, iron chloride, silver 

 nitrate, chromic acid, tin chloride produce a blue pre- 



